Real-time binaural audio rendering in the near field

This paper considers the problem of 3-D sound rendering in the near field through a low-order HRTF model. Here we concentrate on diffraction effects caused by the human head which we model as a rigid sphere. For relatively close source distances there already exists an algorithm that gives a good approximation to analytical spherical HRTF curves; yet, due to excessive computational cost, it turns out to be impractical in a real-time dynamic context. For this reason the adoption of a further approximation based on principal component analysis, which can significantly speed up spherical HRTF computation, is proposed. The model resulting from such an approach is suitable for future integration in a structural HRTF model and parameterization over anthropometrical measurements of a wide range of subjects.